236 ANATOMY OF THE LOWER EXTREMITY. 



of the fibula, where it curves around that bone, passing between il 

 and the peroneus longus muscle, dividing, as it disappears, into th< 

 anterior tibial and musculo-cutaneous nerves. The peroueal nerv< 

 before disappearing, besides giving off a few small cutaneous, mus- 

 cular, and articular branches, furnishes an important snperficii 

 branch, the comiimnicans peronei ; this passes down upon the outer 

 side of the call of the leg to about its middle, where it is joined by a 

 branch from the popliteal, called the conimunicans poplitei, and the 

 two, uniting, constitute the external, or short sapheua nerve. This 

 union does not always, however, take place, one of the nerves losing 

 itself in the integument, and the other, continuing downward, pursues 

 the course and takes the name of the short saphena nerve. 



The popliteal nerve lies superficial to the popliteal vein, and, at the 

 lower border of the popliteal space, becomes the posterior tibial nerve ; 

 while in the space, it gives off muscular branches to the heads of the 

 gastrocnemius muscle, an articular branch to the interior of the knee- 

 joint, and a superficial branch, called the cominunicans poplitei ; this is 

 larger than'the communicans peronei, with which, after passing be- 

 tween the two heads of the gastrocnemius, it unites, half-way down 

 the leg ; their union constitutes- the external, or short saphena nerve. 

 This nerve descends the leg on the outer side of the tendo Achillis, 

 curves round the outer malleolus, and is distributed to the outside of 

 the foot and little toe. 



The POPLITEAL YEIN lies upon the popliteal artery, and 

 receives the external saphena vein, which, after a superficial 

 course up the back of the leg, here penetrates to terminate 

 in the popliteal vein. 



The POPLITEAL ARTERY lies deeply imbedded in the 

 popliteal space; it is the continuation of the femoral 

 artery; commencing at the point where that vessel 

 emerges, after passing through the opening in the tendon 

 of the adductor magnus muscle, it terminates at the lower 

 border of the popliteus muscle, by dividing into the ante- 

 rior and posterior tibial arteries ; this division sometimes 

 takes place at a point higher up. 



The popliteal artery gives off four articular branches, 

 viz : superior and inferior external articular, and superior 

 and inferior internal articular. These wind around the 

 knee-joint to its front, supplying the lower part of the 

 femur, the heads of the tibia and fibula, and the joint 

 itself; they anastomose very freely with each other, with 

 the anastomotica magna, and the recurrent branch of the 

 anterior tibial artery. The inferior articular arteries pass 

 beneath the lateral ligaments of the knee-joint, and the 

 superior articular beneath the tendon of the biceps on the 

 outside, and that of the adductor magnus muscle on the 

 inside. Two large muscular branches, called the sural, pass 



